Losing your temper wins the moment and loses the relationship. Bad trade every time.

Anger is persuasive right now and expensive later. You get the last word, the room goes quiet, and something shifts in how that person deals with you afterwards, usually by telling you less and trusting you less. Nobody announces the change, which is why the trade looks good in the moment and terrible across a year.

When your chest goes tight, buy yourself sixty seconds. Leave the room, get some water, say you will come back to it. You can still say the hard thing later, and it lands better without the volume.